1. Field of the Invention
The invention lies in the field of printing presses. The present invention relates generally to a sheet-conveying apparatus, for example, for conveying newspapers, and, more particularly, to a sheet conveying apparatus having pockets moving on a track. In particular, the invention relates to a lap separator for separating forward and rearward laps of a folded first sheet material section in a pocket to allow nesting of a second section therein and a method for separating such laps.
2. Background Information
Sheet-conveying devices, in particular, devices for conveying newspapers, are required to be able to insert or nest or collate various sets of sheets inside one another. Specifically, to create a finished newspaper, a first folded section of the paper, taking the form of a folded sheet section, is opened and at least one second section of the newspaper is inserted between the two sides of the folded sheet section. It is possible that the second section is, itself, a section having third, fourth, or more other sections nested therein in the same manner as the first section. To process such sheets, in particular, newspapers, prior art conveying devices have an angle-shaped pocket that first picks up a first section, opens the first section, and then conveys the opened first section to a delivery station. Prior art systems including pockets include, for example, U.S. Pat. No. 4,133,521 to Mxc3xcller and U.S. Pat. No. 5,213,318 to Newhall. A delivery unit drops the second section into the opened first section to create a nested paper with two sections. This process can be repeated for many different sections to create an entire newspaper.
There is a difficulty associated with the pocket properly opening the first section to the appropriate opening position. To facilitate proper opening, each section is formed with a lap. In other words, the two ends of the folded sheet section are not even. Typically, in a sheet-processing direction, the forward-most end of the folded sheet section is longer than the rear-most end of the folded sheet section. Thus, if the fold of the sheet section is at the bottom of the pocket, when viewing the ends of the folded sheet section in the pocket from above, the forward lap is higher than the rear lap.
In such a position, the folded sheet section can be opened if the forward, higher lap is secured by a device (applying a physical contact and/or air suction) and the pocket or folded sheet section is moved or tilted to allow gravity (possibly assisted with suction) to let the rear lap fall away from the forward lap. After the rear lap has fallen or is moved away from the forward lap, there exists an opening into which a second section can be inserted. Accordingly, a second section can be inserted into or nested within the first section. This combined section can then be inserted into a further section, and so on, to create a multiply nested set of sheets, typically, forming a common newspaper.
The securing device typically takes the form of a finger-shaped gripper. In the opening process, such a gripper is rotated or lowered onto the forward lap to secure the forward lap, and the forward sheet section, to a front wall of the pocket. Some examples of prior art gripper systems in such pockets include U.S. Pat. No. 4,723,770 to Seidel et al., U.S. Pat. No. 4,988,086 to Schlough, and U.S. Pat. No. 5,024,432 to Thxc3xcnker et al.
U.S. Pat. No. 5,911,416 to Klopfenstein describes a sheet material conveying apparatus with a plurality of pockets moveable around a track to accept sheet material from sheet material feeders. These pockets permit, for example, a first outer section of a newspaper to first be fed into the pockets by a first sheet material feeder, and then an inner newspaper section to be inserted between the folds of the first outer newspaper section. The Klopfenstein apparatus uses a lift cam 20 to move a semicircular actuator gear 150 to rotate a drive shaft 110 so as to set a height for pocket feet 90 disposed on racks 80. A pawl and ratchet mechanism prevents the pocket from opening. The sheet material can then be accepted and inserted into the pockets. To deliver the sheet material, a trip cam 22 can release the pawl and ratchet mechanism. Tracks 80 move to a lower position through a biasing spring, so that feet 90 release through operation of a driver cam 130. The sheet material in the pocket can, thus, move out of the pocket from the bottom to be further conveyed or to be stacked. The entirety of Klopfenstein is hereby incorporated by reference.
U.S. Pat. No. 5,251,888 to Eugster purports to describe pockets moveable along an endless path. Each pocket is provided with two vertically adjustable stops 14 mounted displaceably in a pocket carrier 8. A guide member 28 purportedly can be set to vertically adjust the stops 14 as the pockets are moved along the endless path.
Because sheet delivery devices travel at relatively high speeds, the window of time for gripping the forward lap is small. Accordingly, there is a need to expand the window of time for gripping the forward lap. Significantly, lap sizes are neither consistent nor equal. Therefore, expansion of the time window must also be able to compensate for variations in lap sizes.
It is accordingly an object of the invention to provide a lap separator for separating forward and rearward laps of a folded first sheet material section in a pocket to allow nesting of a second section therein and a method for separating such laps that overcome the hereinafore-mentioned disadvantages of the heretofore-known devices and methods of this general type and that expands the time window for separating the forward lap from the rearward lap while also accommodating variations in size of forward and rearward laps.
Commonly assigned U.S. patent application Ser. No. 09/662,277, entitled xe2x80x9cSHEET MATERIAL CONVEYING APPARATUS WITH INDIVIDUALLY-ADJUSTABLE POCKETSxe2x80x9d filed on Sep. 14, 2000, describes a plurality of manually-adjustable pockets, each having a setting device for adjusting a height of the pocket.
Commonly assigned U.S. patent application Ser. No. 09/702,012, entitled xe2x80x9cSHEET MATERIAL CONVEYING APPARATUS WITH HEIGHT-ADJUSTABLE POCKETSxe2x80x9d filed on Oct. 30, 2000, describes a plurality of manually adjustable pockets, each having a setting device for adjusting a height of the pocket so as to define a set height.
Commonly assigned U.S. patent application Ser. No. 10/178,645, entitled xe2x80x9cADJUSTABLE GRIPPING DEVICE FOR ADJUSTABLE SHEET RECEIVING POCKETS AND METHOD FOR ADJUSTING SHEET RECEIVING POCKETSxe2x80x9d and filed concurrently herewith, describes a different gripper adjusting system 70 having an adjustable gripper 71 with two main parts, a gripper body 72 and an adjustment device 73 including a pivot 75, a cam follower 77, and an adjustment body 79 in the form of a two-arm rocker. Depending on a placement setting of a vertically adjustable cam 26, the adjustment body 79 pivots and moves a nose 74 of gripper body 72 along the surface of upper front wall 52 away from or towards the uppermost edge of the rearward lap 63.
Commonly assigned U.S. patent application Ser. No. 10/178,645 entitled xe2x80x9cADJUSTABLE GRIPPING DEVICE FOR ADJUSTABLE SHEET-RECEIVING POCKETS AND METHOD FOR ADJUSTING SHEET-RECEIVING POCKETSxe2x80x9d and filed concurrently herewith, describes a different gripper adjusting system 70 where each gripper 71 is individually adjustable through a gripper plunger 73 having a plunger body 75 with a nose, a rod 76, and a cam follower 77 attached to the end of rod 76. The nose directly contacts and holds forward lap 61 of a section 6, or holds the entire section 6, 61, 63. Depending on a setting of a vertically adjustable cam 26 the nose moves away from or towards an upper edge of the rearward lap 63.
Each of these commonly assigned applications are hereby incorporated by reference herein.
With the foregoing and other objects in view, there is provided, in accordance with the invention, a lap separator system for opening a sheet in a pocket traveling in a transport direction at a given speed, the pocket having forward and rearward walls pivotally connected to one another, the forward and rearward walls together defining an opening for receiving the sheet, the lap separator system including a moveable separator carrier, at least one separator connected to the separator carrier, the separator carrier adapted to convey the at least one separator in the transport direction along the pocket at a speed greater than the given speed, and the at least one separator adapted to sequentially contact the rearward wall, the sheet in the pocket, and then the forward wall and to sequentially release the rearward wall, at least a portion of the sheet in the pocket, and then the forward wall.
In accordance with another feature of the invention, the separator is adapted to sequentially release the rearward wall, at least a portion of the sheet in the pocket, at least another portion of the sheet in the pocket, and then the forward wall.
In accordance with a further feature of the invention, the track has elevational change sections for displacing the separator with respect to the pocket. Preferably, the sections include inclines for displacing the separator away from the pocket and/or declines for displacing the separator towards the pocket.
In accordance with an added feature of the invention, the separator carrier is a track, preferably, an endless track.
In accordance with an additional feature of the invention, the separator is a plurality of separators. Preferably, the separator is of a flexible material. The separator can be a brush, a finger-shaped extension extending towards the pocket, a row of finger-shaped extensions each extending towards the pocket, a cylindrical rod, and/or a rectangular column.
With the objects of the invention in view, there is also provided a sheet-opening system, including at least one moveable pocket having forward and rearward walls pivotally connected to one another, the forward and rearward walls together defining an opening for receiving at least one sheet, the at least one pocket adapted to travel in a transport direction at a given speed and a lap separator system for opening the at least one sheet in the pocket, the separator system having a moveable separator carrier, at least one separator connected to the separator carrier, the separator carrier adapted to convey the at least one separator in the transport direction along the at least one pocket at a speed greater than the given speed, and the at least one separator adapted to sequentially contact the rearward wall, the at least one sheet in the pocket, and then the forward wall and to sequentially release the rearward wall, at least a portion of the at least one sheet in the pocket, and then the forward wall.
With the objects of the invention in view, there is also provided a sheet-collating machine, including a conveyor adapted to travel in a transport direction at a given speed, at least one sheet feeding device disposed at the conveyor for feeding at least one sheet towards the conveyor, pockets each having forward and rearward walls pivotally connected to one another, the forward and rearward walls together defining an opening for receiving the at least one sheet, each of the pockets connected to the conveyor, adapted to receive the at least one sheet from the at least one sheet feeding device, and adapted to transport the at least one sheet along at least a portion of the conveyor in the transport direction, and a lap separator system for opening the at least one sheet in at least one of the pockets, the separator system having a moveable separator carrier, at least one separator connected to the separator carrier, the separator carrier adapted to convey the at least one separator in the transport direction along the at least one pocket at a speed greater than the given speed, and the at least one separator adapted to sequentially contact the rearward wall, the at least one sheet in the pocket, and then the forward wall and to sequentially release the rearward wall, at least a portion of the at least one sheet in the pocket, and then the forward wall.
In accordance with yet another feature of the invention, the separator carrier and/or the separator are adjustable in a vertical direction with respect to the pockets.
With the objects of the invention in view, there is also provided a method for opening a sheet within at least one sheet-receiving pocket of a sheet-collating device, including the steps of conveying the at least one sheet-receiving pocket along a transport path in a transport direction at a given speed, the pocket having forward and rearward walls pivotally connected to one another, the forward and rearward walls together defining an opening for receiving the sheet, placing the sheet in the at least one sheet-receiving pocket, conveying at least one separator on a separator carrier along a second transport path in the transport direction at a speed greater than the given speed, and sequentially contacting the rearward wall, the sheet in the pocket, and then the forward wall with the at least one separator and then sequentially releasing the at least one separator from the rearward wall, at least a portion of the sheet in the pocket, and then the forward wall.
In accordance with yet a further mode of the invention, the pocket is a plurality of pockets and the separator is a plurality of separators.
In accordance with yet an added mode of the invention, the second transport path is adjacent and/or follows the transport path.
With the objects of the invention in view, there is also provided a method for opening a sheet within a sheet-receiving pocket, including the steps of providing sheet-receiving pockets to be conveyed in a transport path, each pocket having forward and rearward walls pivotally connected to one another, the forward and rearward walls together defining an opening for receiving the sheet and displacing at least one separator to sequentially contact the rearward wall, the sheet in the pocket, and then the forward wall and then to sequentially release the at least one separator from the rearward wall, at least a portion of the sheet in the pocket, and then the forward wall.
xe2x80x9cRodxe2x80x9d as defined herein can be any elongated structure.
Other features that are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a lap separator for separating forward and rearward laps of a folded first sheet material section in a pocket to allow nesting of a second section therein and a method for separating such laps, it is, nevertheless, not intended to be limited to the details shown because various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.